骨密度（超音波法）の意義と改善方策に関する研究

The Meaning of Bone Mineral Density by Ultrasound Method
and its Betterment

by

Yoshibumi Nakahara, Jun Kitagawa
Graduate School of Decision and Science and Technology,
Tokyo Institute of Technology
Tadaharu Adachi
Faculty of Engineering, Tokyo Institute of Technology
Toshitada Yoshioka
St. Marianna Medical school

ABSTRACT

Calcium was given to male college students who showed lower bone mineral density (BMD) with the ultrasound bone densitometer (Achilles, Lunar) for two months. Subjects were divided into two groups ; calciumfood supplement group (Ca group,n=6) and milk calcium supplement group (Milk group, n=4). Then the changes of ultrasound parameters were examined before and after supplementation. In the Milk group , the change of BMD on lumbar spine (LS) was simultaneously measured using DXA (DPX-L, Lunar).
Inhibitory effect on the decrease of speed of sound (SOS) was found in the Ca group. Stiffness,
SOS and BMD on LS were tended to be increased in the Milk group. Broadband ultrasound attenuation (BUA) was not changed in each group.
These results suggested that supplementation of was more effective on improving in BMD than in bone structure.

　要　旨

　超音波法による骨密度が低い傾向にある男子学生に２カ月間Ｃａを付加した。対象者を２群に分け
一方にはＣａ補助食品（Ｃａ群、６名）を、他方には牛乳Ｃａ（牛乳群、４名）を付加した。付加前後において、超音波計測値の変化を検討した。牛乳群ではＤＥＸＡ法による腰椎骨密度変化も同時に測定した。
　Ｃａ群では超音波伝播速度（ＳＯＳ）の低下を抑制する効果を示した。牛乳群ではＳｔｉｆｆｎｅｓｓ、ＳＯＳ
腰椎骨密度が増加する傾向を示した。超音波減衰係数（ＢＵＡ）は両群とも変化しなかった。
　これらの結果から、Ｃａ付加は骨梁構造よりも骨密度の改善に影響を及ぼすと思われる。